1. Field of the Invention
The present invention relates to a tape carrier package, and more particularly to a foldable tape carrier package which electrically connects an LCD panel with an LCD driver printed circuit board. Further, the invention relates to an LCD module to which the tape carrier package is applied.
2. Description of the Related Art
In thin film transistor liquid crystal display (TFT-LCD), gate driver printed circuit board (PCB) that drives gate lines and source driver PCB that drives source lines are respectively disposed apart by a selected distance from long and short edges of LCD panel.
Tape carrier packages (hereinafter referred to as “TCP”) are used for electrically gate and source driver PCBs with LCD panel apart from the PCBs.
TCP is a kind of packages wherein input and output lines, that is, leads are printed on a flexible insulating base film and a chip that is connected with the leads is mounted on the base film. The leads are covered with a resist film except for a selected portion from the both ends.
When gate and source driver PCBs that are connected with the TCP are placed on the same plane with the LCD panel in the LCD module product, the module size becomes larger unnecessarily compared with the display region of the LCD module. Accordingly, it has been provided that such the PCBs are attached to the backside of the LCD panel using the flexibility of the TCP.
Fukuta et al (U.S. Pat. No. 5,153,705, TAB PACKAGE AND A LIQUID-CRYSTAL PANEL UNIT USING THE SAME, Oct. 6, 1992) discusses a TCP in which slit is formed at a bending portion of the TCP in order to prevent leads from being broken when a large stress is concentrated on the bending portion.
As the number of leads increases due to the request of high definition in image quality and of decrease in fabrication costs, pitch between leads decreases. Decrease in pitch enhances the stress per unit area applied to the boundary between a first portion where the resist film is coated and a second portion where the resist film is not coated. As a result, in spite of the existence of the slit, a progressive crack frequently occurs at the boundary.